Enthusiastic Mechanaut

Flying
Artifact spells you cast cost {1} less to cast.

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Great Furnace

Jhoira, Ageless Innovator

{T}: Put two ingenuity counters on Jhoira, Ageless Innovator, then you may put an artifact card with mana value X or less from your hand onto the battlefield, where X is the number of ingenuity counters on Jhoira.

Darksteel Citadel

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

Seat of the Synod

Master Transmuter

{U}, {T}, Return an artifact you control to its owner's hand: You may put an artifact card from your hand onto the battlefield.

Silverbluff Bridge

Silverbluff Bridge enters tapped.
Indestructible
{T}: Add {U} or {R}.

Corridor Monitor

When Corridor Monitor enters, untap target artifact or creature you control.

Padeem, Consul of Innovation

Artifacts you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)
At the beginning of your upkeep, if you control the artifact with the highest mana value or tied for the highest mana value, draw a card.